Conventionally, a motor and an inverter circuit controlling the drive of the motor are positioned close to each other. Such a configuration is known for example, in a Japanese Laid-Open Patent Document No. 2003-153552, (patent document 1) in which a case that houses a circuit board, or a substrate, having an inverter circuit mounted thereon is attached to an outer shell of a compressor.
The patent document 1 discloses a configuration in which an electric power controller semiconductor is mounted on a first circuit board and an Integrated Circuit (IC) chip is mounted on a second circuit board. Further, a plurality of IC chips are mounted in a row on one surface of the second circuit board. That is, as disclosed in the patent document 1, relatively-large-size elements, such as an Application-Specific Integrated Circuit (ASIC), a microcomputer or the like, in a row arrangement requires a large mounting surface on the circuit board, and the constraints such as a diameter of the driver unit make it necessary to split one row arrangement of the large-size elements into two circuit boards (i.e., two substrates).